Preparation And Properties Of Novel Natural Polymeric Polysaccharide Smart Hydrogel Biomaterials

As a tissue engineering scaffold,the hydrogel can be prepared by natural chitosan,which can solve the current practical problems.For example,the biocompatibility of non-natural chemical polymer hydrogel is low,and the mechanical property of the natural polysaccharide hydrogel is also weak.In order to solve the above problems,we used chitosan as raw material,and the way of secondary modification was carried out in this study.Three kinds of new hydrogel forming factors were designed and synthesized.The performance of hydrogel which possessing the new structure was studied.For instance,swelling performance,rheological property,degradation performance,biocompatibility and other material properties.This study provides a theoretical basis for the development of the new bio-scaffold materials.It is a new way to broaden the natural polysaccharide biological applications.The main contents are as follows:(1)The chitosan was modified with furan groups(Furan);(2)The chitosan was modified with other groups(hydrophilic group/ catechol).The structures of the hydrogel forming factors were characterized by FT-IR,1H NMR and XRD.They were furanyl chitosan(FC),carboxymethyl furanyl chitosan(N,O-FC)and catechol furanyl chitosan(Catechol-FC).The Diels-Alder(DA)bond was introduced into the hydrogel structure by using ultrasonic-assisted method.The HN = CO and metal ion complex template were used to form hydrogel.These hydrogels have novel structures,high biocompatibility and intelligent performance.They were as follows:furanyl chitosan hydrogel(FC-PEG),carboxylated chitosan(FC-PEG),N,O-carboxylated furanyl chitosan mono-/di-crosslinked hydrogels(N,O-FC-PEG SN/DN),catechol furanyl chitosan mono-/di-crosslinked hydrogels(Catechol-FC-PEG SN/DN).The surface structure,the swelling property and the mechanical property of hydrogel were investigated by DSC,TGA,UV-Vis and SEM.The hydrogel structure and mechanical property were related to its swelling performance.Among them,N,O-FC-PEG DN has the acid resistance,Catechol-FC-PEG DN has anti-EDTA properties and p H response characteristics.N,O-FC-PEG DN and Catechol-FC-PEG DN have self-healing properties.The mechanical property of DN hydrogel are better than SN hydrogel.In this way,we establish the connection among gelation mechanism,preparation method and the target performance.Based on the above study,we carried out the cytotoxicity and fluorescence analysis to explore the biocompatibility of the target hydrogel.Simulated biological environment under loading and packaging cell culture for a long time,the cells still maintain strong growth.In this study,we synthesized new hydrogels which have superior performance.For example,biocompatibility,mechanical property,safety and self-healing performance.It can be used as a bionic structure model.